This invention relates to a plate hold-down and vibration suppression device adapted for positioning close to and uniformly along a line of cut. More particularly, the invention is concerned with a plate hold-down member which can be positioned parallel to the line of cut and which will eliminate or reduce vibrations in the plate.
In order to cut a plate with an abrasive cutting wheel, it is desirable that the plate be as flat as possible so as to avoid plate vibrations.
Heretofore, the plate was edge clamped onto the work table. Another method of holding the plate onto the table was by means of a heavy weight which was transported to the work table by a crane and placed onto the plate prior to cutting. Some of the problems in connection with the abrasive cutting of plates is that even with the use of edge clamps or a heavy weight there is an inadequate and unsatisfactory hold-down of the plate along the cutting line. This results in plate vibration which causes excessive abrasive wheel wear and/or slow cutting rates.
The life of the cutting blade is decreased due to plate vibrations. In addition, because of the bouncing of the plate during cutting, an uneven or non-smooth cut can result. The edge clamps which are used to clamp the plate down also have a tendency to mar the surface of the plate. When the plate is clamped, it is generally difficult to remove all of the bows in the plate. Plates with bows or wavy patterns must also be weighted down by heavy weights which can only be transported by means of a heavy crane. This requires a great deal of excess floor space in order to move the crane into and out of position so as to place the weights onto the plate.
One purpose of the invention is to provide a plate hold-down member which will prevent plate vibration by massive loading of the plate distributed over much of its surface and thereby absorb and damp plate vibrations.
Another purpose of the invention is to provide for a plate hold-down member which will not mar or deface the surface of the plate.
A further purpose of the invention is to provide means for rapidly applying and removing a load without the use of a crane.
Another purpose is to reduce the wear of the abrasive cutting wheel.
In order to accomplish the foregoing purposes and object, the invention provides for a flexible expansible and retractable liquid tight container which can be readily and simply placed onto the plate. The container is attached to a pump and source of liquid supply. The container is filled with a liquid, and as it is being filled it expands and moves out along the plate. The container is expanded so that it extends along the entire length of the plate onto the table. By suitable arrangements, it is possible to position the liquid-filled container close to and parallel to the cutting line.
Depending upon the size of the plate and the width of the container, one or more expansible containers can be used for placement on top of the plate to hold the plate down and prevent vibration. The filled containers will provide the massive, distributed, vibration absorbing hold down on the cutting table. In addition, for thinner plates, the weight of the liquid-filled container will remove much of the bow of the plate.
Other advantages and the nature of the invention will become readily apparent from the detailed description of the invention and the drawings thereof in which a preferred mode and embodiment thereof is disclosed.